A communication network typically authenticates a registration request from a mobile node before allowing the mobile node to register with the network. As an example, an Internet Protocol (IP) network may authenticate a registration request from a mobile node before allowing the mobile node to register with the IP network. Authentication may involve establishing whether there is a security association between the mobile node and a gateway of the network. The absence of a security association may prohibit the registration request from being authenticated.
According to a known authentication technique, a gateway of a network may perform a challenge procedure with a mobile node. In a challenge procedure, the gateway may send a challenge to the mobile node. If the mobile node fails respond in the appropriate manner, the registration request is not authenticated. These known techniques for authenticating a registration request, however, are not efficient in certain situations. It is generally desirable to efficiently authenticate a registration request in certain situations.